Process for the recovery of glycerin



. Patented Apr. 11, 1 939 um'rsn STATES- PATENT OFFICE rnocnss 'roa 'rnnmicovnay or cpycnam Karl Werner, Neu Ise nburg, Frank! n41..- assignorto ort-o Dentsche Gold- I Ge s und Silber-Scheidcanstalt vormalsBoessler, a corporation of Germany No Drawing.

Application July 1c, 1938, Serial No.

In Germany July 16, 1937 6 Claims. (Cl. 260-637) The present inventionrelates to an improved process for the recovery of glycerin frommixtures containing glycerin obtained by the fermentation of vinasse,sugars or other carbohydrate- 5 containing substances.

uors and extractio n of the liquors have previously been used but foundimpracticable. The known extraction processes are not praczo ties] asthe previously employed extracting agents the resulting liquor,containing, for 'example, 30% water, with pyridine in apparatus 7suitable for the extraction ofliquids.

It is possible to obtain a substantially complete separation of theglycerin from the other mate-- rials contained in the fermentationproduct by such extraction with pyridine. The actual yield extractioncountercurrently, as for example, as a in the diffusion batteriesemployed in the sugar industry. The extraction agent, pyridine, employedin accordance with the present invention, need not 5 be in absolutelypure form. It is possibl ploy crude pyridine and mixtures containingarate from glycerin by distillation. l

drawing the water or by azeotropic distillation. l

possesses the commercial requirements after a I the process is carriedout in the manner specified.

fractionated under vacuum.

The following example serves to illustrate the A- fermented vinasse ofthe following general composition was employed:

. Percent Water--- 30 to Glycerin Betaine-like impurities. 15 Otherimpurities including salts 20 to 35'Thismaterialwastreatedwithpyridineina dilution with water 25 2 startingmaterial. The. glycerin 1'10 0. to 200 c The glycerin btained wasfurther purified by the following treatment:

distilled over at 5 The raw glycerin containing about 15% water wasdiluted with an equal volume of water and heated to the boiling point.The boiling hot solution was then filtered through 10 grams ofdecolorizlng charcoal in a filtering funnel'heated with boiling water.This decolorizing treatment and a substantially colorless product wasobtained. By the concentration of this aqueous glycerin solution, aglycerin was obtained which meets the requirements of dynamite glycerin.

while I have described herein some embodiments of my invention, 1 wishit to be understood that I do not wish to limit myself thereby exceptwithin the scope of the appended claims. 20 I claim:

1. In a process for the recovery of glycerin from fermentation productscontaining glycerin, the step comprising extracting the glycerin fromsuch products with pyridine.

2. In a process for the recovery of glycerin from aqueous mixturescontaining glycerin and betaine-like substances, the step comprisingextracting the glycerin from such mixtures with pyridine.

3. In a process forthe recovery of glycerin from fermented vinassecontaining glycerin in admixture with other products of fermentation,the step such mixtures with pyridine.

4. In a process for the recovery of glycerin from aqueous fermentationproducts containin glycerin, the step comprising extracting the glycerinirom such aqueous products with pyridine.

5. In a process for the recovery of glycerin from aqueous fermentationproducts containing glycerin, the steps comprising adjusting the .watercontent of such products to 30-35% and then extracting the glycerintherefrom with pyridine.

6. In a process for the recovery of glycerin from-fermentation productscontaining glycerin, the steps comprising extracting such products withpyridine, distilling the extract to recover the glycerin containedtherein, diluting the recovered glycerin with water, heating the dilutedglycerin and contacting such heated solution with activated charcoal.

KARL WERNER.

comprising extracting the glycerin from

